BTW you can speed up cloud-init to look for CloudStack first/only by overriding the datasource_list. The way I do it is by adding a file in my templates to the /etc/cloud/cloud.cfg.d directory with only CloudStack in it:
echo "datasource_list: [ CloudStack ]" > etc/cloud/cloud.cfg.d/90_datasource.cfg Start to finish on a first time boot of an instance cloud-init takes ~12 seconds on my system. A reboot of that same system, cloud-init only takes 5 seconds. This is with a default/stock cloud-init config on an ubuntu 14.04 system with just that one file added. On Wed, Aug 5, 2015 at 10:46 PM, Chiradeep Vittal < chiradeep.vit...@citrix.com> wrote: > Today the metadata / userdata server is retrieved by the guest from > http://<address of DHCP server>/latest/meta-data and > http://<address<http://<address> of DHCP server>/latest/user-data > > This of course has been inspired by the EC2 standard[1] > http://169.254.169.254/latest/ > > While this works and has been incorporated into cloud-init [2], there are > other platforms that do not use cloud-init and consume the > userdata/metadata directly. For example, CloudFoundry [3] does not use > cloud-init, rather it tries to have adapters for different cloud types. > Adding support for CloudStack in this case can take a long time. > Another problem is that cloud-init tries the ec2 way first, times out and > then tries the CloudStack way. > > I found a easy way to get the EC2-style metadata addressing working in > Advanced Zone / Isolated / VPC > > By adding the following iptables rule in the VR, the guest VM can safely > address the 169.254.169.254 URL > iptables -t nat -A PREROUTING -i eth0 -p tcp -m tcp --dport 80 -d > 169.254.169.254/32 -j DNAT --to-destination <eth0 ip:80> > > > The current addressing scheme continues to work while supporting the EC2 > scheme. > Since the VR is not on the default router in Basic Zone and other cases, > this is not universally applicable. > For KVM & XenServer in Basic Zone we could program the iptables rules in > dom0 (host) to NAT 169.254.169.254 queries to the DHCP server. > > For XenServer in Advanced Zone where OVS is the default, there is no > stateful NAT possible. > For other hypervisors (Hyper-V, VMWare) and Baremetal, there is no > comparable solution for Basic Zone and advanced networks where the VR is > not the default router. > > > However, note that this is not a breaking change, rather, an enhancement. > > Thoughts? > — > Chiradeep > [1] > http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ec2-instance-metadata.html > [2] https://cloudinit.readthedocs.org/en/latest/ > [3] > https://github.com/cloudfoundry/bosh-agent/blob/master/settings/settings.go > >
